ASME Sec. IX, paragraph QW-202.6(a) allows welded tube-to-tubesheet joint to be qualified to QW-202.2 and QW-202.4 (if QW-193.1 isn't mandatory by construction Code).
"QW-202.2(b) Qualification for Partial Penetration Groove Welds" says, to my understanding, that there is no maximum thickness limit of base metal thickness provided the PQR coupon was a minimum of 1-1/2" thick. Does this mean that if we were to weld a PQR coupon with a full penetration groove on 1-1/2" thick material, and it passed required mechanical tests of Table QW-451.1, this PQR could be used to support a WPS for welding tube-to-tubesheet joints (any of the figures shown in ASME Sec. VIII-1 Fig. UW-20.1) with base materials ranging from minimum 3/16" thickness (assuming supplementary essential variables are N/A) to unlimited maximum tubesheet thickness?
If the tubes are thinner than 3/16" (0.065" nom. for example) , we would just need to weld a second coupon with T of 3/8" or less. Is this correct?
"QW-202.2(b) Qualification for Partial Penetration Groove Welds" says, to my understanding, that there is no maximum thickness limit of base metal thickness provided the PQR coupon was a minimum of 1-1/2" thick. Does this mean that if we were to weld a PQR coupon with a full penetration groove on 1-1/2" thick material, and it passed required mechanical tests of Table QW-451.1, this PQR could be used to support a WPS for welding tube-to-tubesheet joints (any of the figures shown in ASME Sec. VIII-1 Fig. UW-20.1) with base materials ranging from minimum 3/16" thickness (assuming supplementary essential variables are N/A) to unlimited maximum tubesheet thickness?
If the tubes are thinner than 3/16" (0.065" nom. for example) , we would just need to weld a second coupon with T of 3/8" or less. Is this correct?
